A Complete Guide To Modular ADUs: Everything You Need To Know

Modular ADUs are gaining traction as a quick and efficient way to build an ADU.

In this guide, we’ll take you through everything there is to know about modular ADUs, from the benefits to the drawbacks and everything in between.

Let’s jump straight into it.

Table of Contents

What is a Modular ADU?

A modular ADU is a prefabricated, factory-built accessory dwelling unit.

These units are constructed off-site and then transported to your property for installation.

This method speeds up the building process and can be more cost-effective than traditional construction.

Benefits of Modular ADUs

Modular ADUs offer many benefits to a homeowner.

Speed Of Construction

Modular ADUs are built faster than traditional homes.

Since they’re constructed in a factory, weather delays are minimized, and it’s much faster to ‘construct’ them once they are on site.

The full process typically takes 8-12 weeks, but can be faster depending on the vendor.

Lower, More Predictable Cost

Prefabrication can lower costs due to bulk purchasing of materials and reduced labor time.

This makes modular ADUs an affordable option for many homeowners, with prices starting around the $50k mark but ranging widely depending on who you choose. Keep in mind that this investment will also increase your property value as well.

There is also a lot less that can go wrong during the build, which means your cost estimate is going to be much more accurate than if you were completing an ADU build from scratch.

Consistent Build Quality

Factory construction ensures consistent quality. Each unit is built under strict supervision, adhering to high standards that might be harder to maintain on a traditional construction site.

Energy Saving & Less Waste

Modular ADUs generate less waste and are often more energy-efficient. They use sustainable materials and processes, reducing the environmental impact.

Design Flexibility

Modular ADUs are super flexible.

If you work with a reputable manufacturer, you can customize your layout and design a lot to get the exact look you want.

Design and Layout Considerations

Modular ADUs can have a lot of different layouts, from open-plan spaces to more separated, private rooms.

These layouts will need to be approved, but the majority of modular ADU manufacturers will create designs with local regulations in mind, which streamlines the entire process.

Cost Considerations

While modular ADUs are generally more affordable, it’s important to consider all costs.

These include the base price of the ADU itself, which varies based on size, design, and features.

Costs for transporting the unit to your site and the installation process are significant as well. Preparing your property for installation, including foundation work and utility hookups, also adds to the total expense.

Even when these extra costs are considered, modular ADUs tend to take the title for affordability.

Regulations and Permits

Like with any type of construction these days, building a modular ADU is not straightforward and requires compliance with various regulations.

Obtaining necessary building permits is obviously a requirement, and the requirements for these vary from location to location.

Check local zoning laws to ensure your property is eligible for an ADU.

Ensure your ADU complies with all local regulations and building codes. Consulting with a professional familiar with local regulations can streamline this process and help avoid potential pitfalls.